gms | German Medical Science

55. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie e. V. (DGNC)
1. Joint Meeting mit der Ungarischen Gesellschaft für Neurochirurgie

Deutsche Gesellschaft für Neurochirurgie (DGNC) e. V.

25. bis 28.04.2004, Köln

Neurofibromatosis Type 2: A challenge for AEP-monitoring in vestibular schwannoma resection

Neurofibromatose Typ 2: eine Herausforderung für das AEP-Monitoring bei Vestibularis-Schwannom-Resektion

Meeting Abstract

Suche in Medline nach

  • corresponding author Katja Kniese - Department of Neurosurgery, Klinikum Hannover Nordstadt, Haltenhoffstr. 41, 30167 Hannover
  • M. R. Gaab - Department of Neurosurgery, Klinikum Hannover Nordstadt, Haltenhoffstr. 41, 30167 Hannover
  • M. Samii - Department of Neurosurgery, Klinikum Hannover Nordstadt, Haltenhoffstr. 41, 30167 Hannover
  • C. Matthies - Department of Neurosurgery, Klinikum Hannover Nordstadt, Haltenhoffstr. 41, 30167 Hannover

Deutsche Gesellschaft für Neurochirurgie. Ungarische Gesellschaft für Neurochirurgie. 55. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie e.V. (DGNC), 1. Joint Meeting mit der Ungarischen Gesellschaft für Neurochirurgie. Köln, 25.-28.04.2004. Düsseldorf, Köln: German Medical Science; 2004. DocDI.02.07

Die elektronische Version dieses Artikels ist vollständig und ist verfügbar unter: http://www.egms.de/de/meetings/dgnc2004/04dgnc0161.shtml

Veröffentlicht: 23. April 2004

© 2004 Kniese et al.
Dieser Artikel ist ein Open Access-Artikel und steht unter den Creative Commons Lizenzbedingungen (http://creativecommons.org/licenses/by-nc-nd/3.0/deed.de). Er darf vervielf&aauml;ltigt, verbreitet und &oauml;ffentlich zug&aauml;nglich gemacht werden, vorausgesetzt dass Autor und Quelle genannt werden.


Gliederung

Text

Objective

Neurofibromatosis Type 2 (NF-2) is a rare inherited disease with bilateral vestibular schwannomas (VS). Hearing preservation is a major goal in the surgical treatment of these patients and might be superior to the general principle of surgical radicality in selected cases. It is highly dependent on reliable and fast electrophysiological monitoring (and the neurosurgeon´s willingness to react on the reported changes).

Study Design

In case of bilateral good hearing, preoperative AEP are considered in the decision on the operation side. In case of the last hearing ear the option for subtotal removal is discussed with the patient, but is decided at surgery on microscopic and monitoring aspects. Monitoring set-up includes Median, Tibial Nerves SEP, cranial nerve EMG, multi-modality monitoring of auditory function by conventional and nearfield AEP.

Results

Within a series of 148 NF-2 patients operated for 187 VS, 134 ears presented with preoperative hearing, 50 of which retained auditory function after tumor resection (37%), 31 after complete and 18 after subtotal surgery. In 26 VS operations AEP was preserved during opening of the auditory meatus and during resection of the tumor mass, but tumorous nerve change or strong adherence would have allowed complete resection only for the price of AEP loss. Therefore, resection was terminated after intrameatal decompression and at AEP preservation. However, 8 patients lost their auditory function within 1 to 10 days after surgery, while 18 maintained useful function for periods up to 13 years, so far. Temporary complete loss of single AEP components predicted the danger of secondary functional loss. The latency from onset of wave changes to wave losses was significantly shorter than in non-NF-2 conditions.

Conclusions

Intraoperative monitoring is a necessary part aiming for hearing preservation in VS-resection, if realistic preconditions are fulfilled by the NF-2 patient.